1. Field of the Invention
The present invention relates to an insulation cap structure for a rotating machine, and more particularly to a novel improvement in facilitation of operation of a winding machine and improvement of productivity, the improvement being achieved by forming corner portions of a tongue of an insulation cap for insulating a coil to be wound around a core into arcuate or C-shaped curved edges and by making a locus of winding of the coil by the winding machine approximately circular.
2. Description of the Related Art
Up to now, the structure shown in FIG. 3 is generally employed as this type of conventional insulation cap structure for a rotating machine.
That is, in FIG. 3, reference numeral 1 denotes a stator core formed by laminating a plurality of stator core pieces la formed in a ring shape. On an inner surface of this stator core 1, a plurality of magnetic poles 2 projecting inwardly are formed at predetermined angle intervals.
The stator core 1 has first and second end surfaces 1A and 1B provided with a pair of first and second insulation caps 3 and 4 made of a resin, and the respective insulation caps 3 and 4 constitute an insulation cap body 5.
Tongues 3a and 4a formed on the inner surface of the respective insulation caps 3 and 4 extend along the axial direction of the stator core 1 and are formed in rectangular shapes as shown in FIG. 4.
Corner portions 10 provided on both sides of the respective tongues 3a and 4a have right-angled shapes, and the respective tongues 3a and 4a are formed in a rectangular shape as a whole with the magnetic pole 2 of the stator core 1 sandwiched, as shown in FIG. 4. Note that portions 20 shown by broken lines in FIG. 4 indicate the thickness of the respective insulation caps 3 and 4.
The conventional insulation cap structure for a rotating machine is constructed as described above, and therefore has the following problem.
That is, since the corner portions of the tongues of the respective insulation caps are formed in a right-angled shape, in the case where a coil is wound around outer peripheries of the respective magnetic poles in this state (that is, in slots between the respective magnetic poles), by means of an automatic winding machine, with the coil being insulated by the respective insulation caps, a rotational locus 30 of a needle of the automatic winding machine for winding this coil takes a rectangular shape as shown in FIG. 4. Therefore, program of a servo system for controlling the operation of the needle is complicated.
Moreover, since a locus of the needle is a square in this way, speeding-up of the operation of the needle itself is restricted, resulting in a serious obstacle to mass production.